SERUM TRANSFERRIN RECEPTOR AS A DIAGNOSIC TEST OF IRON DEFICIENCY ANEMIA IN THE HOSPITALIZED PATIENTS (WEST OF ALGERIA)

Iron deficiency remains a major public health problem, affecting over 1.5 billion people worldwide. Widely used tests of iron status include serum ferritin, soluble transferrin receptor (sTfR), and other indices such as transferrin and transferrin saturation.

However, both ferritin and transferrin proteins are markedly influenced by inflammation, behaving as acute-phase reactants and making it difficult to differentiate between iron-deficiency anemia (IDA) and anemia of chronic disease (ACD) occurring with infection or malignancy. Determination of serum soluble transferrin receptor (sTfR) is proposed to distinguish between iron-deficiency anemia and anemia of chronic disease.

Aim: The aims of our study are to affirm the value and specificity of sT-fR and integrate it in the list of routine parameters of iron status in the differential diagnosis of anemia in our laboratories in Algeria.

Patients and Method: Our study included 130 patients divided into three groups: control group with 40 healthy adult (22 men and 18 women). Group 2, with 30 patients (11 men and 19 women) hospitalized at the hematology department of the University Hospital “Abdelkader Hassani” of Sidi Bel Abbes (west of Algeria), which represents the group of subjects with purely iron deficiency anemia without any associated disease (IDA) having rates of C-reactive protein (CRP <10 mg / L), and the third group with 60 anemic patients with anemia of chronic disease (ACD) (36 men and 24 women) hospitalized at the department of Internal Medicine of the University Hospital of Sidi Bel Abbes.

Each patient underwent a complete blood count, an iron status, and the sT-fR assays, and inflammatory balance (CRP). All these examinations were performed immediately on fresh plasma and serum; assays were performed by immune turbidimetric method.

Statistical analyzes of the data (mean and standard deviation, correlation coefficients, tests for normality and comparison of means) were performed using the software Statview (1998).
A P-value (P <0.05) was considered statistically significant, all P values ​​are calculated by the t-test function using bilateral distribution.

Results: The control group (healthy subjects) has a normal iron status. All parameters with levels in normal ranges in both sexes for 100% of subjects.

The outcome of the second group is in perfect agreement with IDA for all of its parameters, it has a very disturbed iron status representative of this anemia: anemia (Hb <120 g/L); microcytosis (MCV <80 fl); circulating pool (serum iron decreased high transferrinemia); reserves depleted (ferritin <30 μg/L) and erythropoietic needs high iron (high sT-fR).

In the third group it's difficult to interpret ferritin levels (very higher), it's in contradiction with the other parameters, which leads us to discuss the homogeneity of this group.

Because there is gender effect on key parameters of our study (hemoglobin, ferritin and sT-fR are heterogeneous in both sexes (P<0.001), the results were analyzed separately between men and women. Analyses of results were done for discussing the sensitivity of the sT-fR on iron status and the informative contribution of each parameter to the specific diagnosis of anemia.

Conclusion: This study has allowed us to recommend for the use of sT-fR assays, because it is very promising for the exploration of erythropoiesis and the differential diagnosis of anemia in adults, with a normal range of: 2.65 to 4.39 mg/L in men and postmenopausal women and 2.03 to 3.69 mg/L in premenopausal women, in the hope of establishing an international range of reference values.